From mboxrd@z Thu Jan 1 00:00:00 1970 From: songjun.wu@microchip.com (Songjun Wu) Date: Thu, 29 Sep 2016 09:21:31 +0800 Subject: [RESEND][PATCH] [media] atmel-isc: start dma in some scenario Message-ID: <1475112091-28120-1-git-send-email-songjun.wu@microchip.com> To: linux-arm-kernel@lists.infradead.org List-Id: linux-arm-kernel.lists.infradead.org If a new vb buf is added to vb queue, the queue is empty and steaming, dma should be started. Signed-off-by: Songjun Wu --- drivers/media/platform/atmel/atmel-isc.c | 9 ++++++++- 1 file changed, 8 insertions(+), 1 deletion(-) diff --git a/drivers/media/platform/atmel/atmel-isc.c b/drivers/media/platform/atmel/atmel-isc.c index ccfe13b..ff403d5 100644 --- a/drivers/media/platform/atmel/atmel-isc.c +++ b/drivers/media/platform/atmel/atmel-isc.c @@ -617,7 +617,14 @@ static void isc_buffer_queue(struct vb2_buffer *vb) unsigned long flags; spin_lock_irqsave(&isc->dma_queue_lock, flags); - list_add_tail(&buf->list, &isc->dma_queue); + if (!isc->cur_frm && list_empty(&isc->dma_queue) && + vb2_is_streaming(vb->vb2_queue)) { + isc->cur_frm = buf; + isc_start_dma(isc->regmap, isc->cur_frm, + isc->current_fmt->reg_dctrl_dview); + } else { + list_add_tail(&buf->list, &isc->dma_queue); + } spin_unlock_irqrestore(&isc->dma_queue_lock, flags); } -- 2.7.4